Going Viral: How Codecademy Snagged 200,000 Users In Seven Days

Zach Sims, 21, and Ryan Bubinski, 22, hang out at their NoHo headquarters.

This article appears in the April 9 issue of FORBES Magazine.

At 3 a.m. one night in mid-December last year, Zach Sims, the 21-year-old CEO of Codecademy, took a break from answering emails and spent $8.95 on the domain name "codeyear.com." Sims, whose company offers interactive online lessons in the programming language JavaScript, decided to take advantage of the New Year by offering the public a timely new resolution: In 2012, learn to code. Within nine weeks 408,000 people took the challenge, receiving a short, weekly lesson throughout the year for only the cost of an e-mail address.

Perhaps only new Apple products can boast a quicker absorption rate. Debuting at 5 p.m. on Jan. 1, Code Year drew 16,000 people in seven hours; by day three, 100,000. “We tried really hard to make the sign up process as frictionless as possible,” says Sims. “It also turns out this was a commitment that people really wanted to share.”

And how. Code Year users flooded Twitter with 50,000 tweets promoting the service in the following weeks – one every second during peak hours. Urged on by influential backers like venture capitalist Fred Wilson, the promotion found unlikely champions in New York City MayorMichael Bloomberg and Washington Post reporter (and Wonkblog editor) Ezra Klein, who, unprompted, hawked the service on Twitter to legions of followers (see chart on next page). This is viral marketing going pandemic.

In February 2011 Sims, a political science major at Columbia University, began Codecademy with classmate Ryan Bubinski, 22, who was studying bio-physics and computer science. The two incubated over the summer at Paul Graham's Y Combinator, which delivered $150,000 in backing.

That helped grab the attention of Wilson's Union Square Ventures, billionaire investor Yuri Milner and superangel Ron Conway, who led a $2.5 million round in October. (Sims won't give up just how much equity that funding bought.) Now with seven employees packed into an office in lower Manhattan's NoHo district, Sims claims 1 million registered users, including the crowd who signed up for Code Year.

The Breakdown: Codecademy's Growth in the First Seven Days

By the end of Saturday, Jan. 7, 199,000 people had signed up for Code Year.

One slight hurdle: None is a paying subscriber.“It’s a natural thing for startups to transition from getting users to generating revenue,” Sims argues, “Not to say that money isn’t a concern.” (Though he'd sooner release his proprietary code as reveal his burn rate.)

Codecademy is considering a variety of ways to monetize, including charging users for premium content like video tutorials and lessons veiled as interactive games. As for the programmers who currently create much of the company’s content gratis? Sims says there may be money in connecting that talent with products, services, even employers - all for a cut.

While Codecademy can't possibly sustain its initial growth spurt, it is getting a lift from endorsements by the Kauffman Foundation and tech giants Foursquare and Twilio. There's also an upcoming partnership with the White House to teach programming to underprivileged youth.